In 2011, roughly 98,960 out-of-state commuters flowed into Oregon for work, up 37% from a decade earlier.

Nearly 81,000 Oregon workers who live out of state, or four in every five, resided in Washington in 2011. Idaho ranked a distant second, with an estimated 6,500 residents commuting into Oregon. About 5,850 Californians were working in Oregon.

The outflow of earnings accounted for one-fifth of the gap between Oregon's per capita earnings and the U.S. average, according to the research.

Washington has the 13th-highest per capita personal income last year. Oregon has the 18th-lowest.